public override void LaunchDialogue()
{
ColorSelectionDialog dialog = new ColorSelectionDialog ("Select a new color");
dialog.ColorSelection.CurrentColor = GetColor ();
dialog.Run ();
dialog.Destroy ();
int red = (int) (255 * (float) dialog.ColorSelection.CurrentColor.Red / ushort.MaxValue);
int green = (int) (255 * (float) dialog.ColorSelection.CurrentColor.Green / ushort.MaxValue);
int blue = (int) (255 * (float) dialog.ColorSelection.CurrentColor.Blue / ushort.MaxValue);
System.Drawing.Color color = System.Drawing.Color.FromArgb (red, green, blue);
//TODO: Property.Converter.ConvertFrom() fails: why?
parentRow.PropertyValue = color;
}